---
title: "Changes to Upload a file"
method: POST
path: "/v1/sessions/{sessionId}/files"
---

# Changes to Upload a file

`POST /v1/sessions/{sessionId}/files`

> Every recorded change to this endpoint, newest first.

## Timeline

Changed in 6 of 54 revisions.

- **2026-06-16** `7b73b0d57792` — 1 breaking
- **2026-06-07** `4985d7bcd32f` — 6 info
- **2026-01-08** `97dcad9b050e` — 2 breaking, 7 info
- **2025-08-11** `15ffd3fc04f3` — 1 breaking, 6 info
- **2025-05-30** `d5a9cdf80ea2` — 1 info
- **2025-05-29** `4d2368c15e4e` — 1 breaking

## Changes

- **2026-06-16** `7b73b0d57792` — 1 breaking
  - request body became required
- **2026-06-07** `4985d7bcd32f` — 6 info
  - added the non-success response with the status `401`
  - added the optional property `linkToDocs` to the response with the `400` status
  - added the optional property `linkToDocs` to the response with the `404` status
  - added the optional property `linkToDocs` to the response with the `409` status
  - added the optional property `linkToDocs` to the response with the `415` status
  - added the optional property `linkToDocs` to the response with the `500` status
- **2026-01-08** `97dcad9b050e` — 2 breaking, 7 info
  - the request property `file` became required
  - the `file` request property contentEncoding changed from `` to `binary`
  - the `file` request property type/format was generalized from ``/`` to `string`/`binary`
  - the response property `context/items/params` became required for the status `400`
  - the response property `context/items/params` became required for the status `404`
  - the response property `context/items/params` became required for the status `409`
  - the response property `context/items/params` became required for the status `415`
  - the response property `context/items/params` became required for the status `500`
  - the `lastModified` response's property pattern `^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d(?::[0-5]\d(?:\.\d+)?)?(?:Z))$` was added for the status `201`
- **2025-08-11** `15ffd3fc04f3` — 1 breaking, 6 info
  - removed the success response with the status `200`
  - added the non-success response with the status `400`
  - added the non-success response with the status `404`
  - added the non-success response with the status `409`
  - added the non-success response with the status `415`
  - added the non-success response with the status `500`
  - added the success response with the status `201`
- **2025-05-30** `d5a9cdf80ea2` — 1 info
  - endpoint added
- **2025-05-29** `4d2368c15e4e` — 1 breaking
  - api removed without deprecation

---

[Operation](https://skmtc.dev/steel-dev/apis/steel-api/docs/v1/sessions/:sessionId/files/post.md) · [API](https://skmtc.dev/steel-dev/apis/steel-api.md) · [Page](https://skmtc.dev/steel-dev/apis/steel-api/changes/v1/sessions/:sessionId/files/post)